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At age 59, NFL Hall of Famer Tony Dorsett is arguably one of the best running backs in the history of professional football. But he, along with NFL All-Pro Leonard Marshall, has been diagnosed with early signs of chronic traumatic encephalopathy (CTE), a degenerative condition that the players attribute to their years of taking hard hits on the field.

"Let me tell you something dude, I can't remember the names of people. Every time I've got to go somewhere, almost every other day, I've got to ask my wife, 'How do I get there?' That is embarrassing," Dorsett told the NY Daily News. "I'm short-tempered and I don't like that. I break down, because I'm like, 'Man, what's happening to me? Why did I just snap at my daughter?'”

According to Boston University’s Center For the Study of Traumatic Encephalopathy, CTE is a progressive degenerative disease of the brain that is usually found in people with a history of repetitive brain trauma. The trauma — in athletes, usually concussions — causes brain tissue to defenerate, which then triggers the buildup of a protein called tau. The buildup of tau, over time, has been linked to symptoms like memory loss, confusion, impaired judgment, impulse control problems, and progressive dementia.

In a moving interview with ESPN, Dorsett detailed how his day-to-day challenges with memory loss and depression have taken a toll. He says his wife and daughters are concerned about his sudden outbursts and trouble controlling his emotions. .

"I've thought about crazy stuff, sort of like, 'Why do I need to continue going through this?'" said Dorsett. "I'm too smart of a person, I like to think, to take my life, but it's crossed my mind."

Dorsett played in the NFL for 12 years and retired from the game over 20 years ago. He is part of a small group of athletes to undergo preliminary testing at UCLA for CTE using brain scan testing that was previously unavailable. For a long time, doctors could only tell if someone had CTE from autopsies after their death, when tau buildup could be seen in the brain upon inspection. However, new research at UCLA shows promise in determining when people have the condition while they’re still alive in order to find ways to reverse it or at least treat it as best they can.

"Until we had the ability to see it in a living, breathing person, we had no chance of helping them, we had no chance of really understanding what happens to the disease. It gives us the ability to track it, to see if it gets worse, or hopefully, maybe it gets better with medication, with intervention, with new discoveries,” said neurosurgeon Julian Bailes, co-director of the NorthShore Neurological Institute in Evanston, Ill. "There's a lot more scientific investigation and rigor and publication and peer review that needs to be done on this, but initially, we're optimistic and excited about the potential of the test."

Until doctors are able to find an adequate treatment, they are encouraging those struggling with symptoms of CTE to remain positive to combat the possible severe effects of the disease. Dorsett says that he’s taking his doctors’ advice.

"I'm trying to slow this down or cut it off," Dorsett said. "I'm going to be 60 years old here next year, so I'm hoping that I've got another good 30 years or so."